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rmcclurk
Jul1-09, 09:20 PM
1. The problem statement, all variables and given/known data

Find limit as z->infinity of exp(z) where z is complex

2. Relevant equations

See above

3. The attempt at a solution

The solution should be that the limit does not exist, but I don't know why. Any explanations?

Dick
Jul1-09, 09:25 PM
Put z=iy, where y is real. Now let y->infinity.

rmcclurk
Jul1-09, 09:30 PM
Is it because e^iy = r(cos(y)+i*sin(y)) and that equation simply oscillates and never goes to infinity no matter how large y gets?

Dick
Jul1-09, 09:33 PM
Is it because e^iy = r(cos(y)+i*sin(y)) and that equation simply oscillates and never goes to infinity no matter how large y gets?

Right, if you put r=1. Or consider z=x and z=(-x) for x real and let x->+infinity. One limit is infinity, and the other is zero. There is no definite single limit as z->infinity. Consider definite cases of z->infinity to get a feeling for what's going on.

rmcclurk
Jul1-09, 10:55 PM
Thanks a lot got it figured out